Fluorescence

Fluorescence microscopy is an imaging technique, which involves illuminating a specimen with filtered excitation light and collecting and filtering the emitted light. This process relies on a chromatic beam splitter that filters the excitation light transmitted through the objective lens onto the sample, as well as filtering the emitted light reflected from the specimen, again through the objective lens. The distinct optical properties allowing for filtration of the excitation and emission light are attributed to photoreactive atoms or molecules within the specimen, which is known as fluorochromes or fluorophores. These fluorescent substances, which can be in the form of stains or dyes, absorb light, energize their electrons, and subsequently release this energy in the form of both heat and light emission, or fluorescence. The emitted light possesses a longer wavelength, lower energy, and a different colour compared to the original absorbed light.

To observe cells using fluorescence microscopy, it is crucial to be familiar with the spectral characteristics of the fluorochrome being utilized. In order to adequately excite the fluorochrome and observe its fluorescent emission, the appropriate chromatic beam splitter or mirror unit must be employed.
The EM Unit provides several mirror units for fluorescent imaging:

U-FUNA: Designed for ultraviolet excitations with an excitation filter range of 360-370 nm and an emission filter range of 420-460 nm. This unit is compatible with the following fluorophores: EBFP, Alexa Fluor 350 & 405, AMCA, Cascade Blue, Monochlorobimane (mBCI), o-phthalaldehyde (OPT), SITS (Primuline), SITS (Stilbene Isothiosulphonic acid), bis-Aminophenyl-oxadizole (BAO)-Feulgen, DAPI, Hoechst 33258 & 33342, 1,8-ANS, DPH, Filipin, Calcein Blue, Fast Blue, Granular Blue, and True Blue.

U-FGNA: Intended for green excitations with an excitation filter range of 540-550 nm and an emission filter range of 575-625 nm. It is suitable for the following fluorophores: DsRed2, RFP (DsRed), Alexa Fluor 532 & 546 & 555 & 568, PE-B, PE-R, RITC, TRITC, Cy3, Resorufin, Ethidium Bromide, Pararosaniline-Feulgen, PI, Pyronin Y, Ethidium homodimer-1, Dil, Lyso Tracker Red DND-99, Mito Tracker Red CMXRos, Nile Red (phospholipid), RH160, RH421, RH423, and Rhodamine-Phalloidin.

U-FBNA: Meant for blue excitations with an excitation filter range of 470-495 nm and an emission filter range of 510-550 nm. It can be utilized with the following fluorophores: Acridine Orange, Acridine Yellow, Alexa Fluor 488, Alexa Fluor 488-Phalloidin, Auramine O-Feulgen, Azami-Green, BCECF, BCECF indicator, BODIPY FL, BODIPY FL Ceramide, BTC, Calcein, Calcium Green, CFDA, Cy2, DiO, DiO C6(3), Dronpa-Green, EGFP, Eosin, Euchrysine, EYFP, Fluo 4, FDA, FITC, FluorX, Fucci (mAG1), GFP (S65T) & (WT), JC-1, Kaede (Green/Red), Midoriishi-Cyan, Mito Tracker Green, NBD-Phallacidin, Oregon Green 488 & 488 BAPTA-1 & 488 BAPTA-5N, PA-GFP, Rhodamine 123, SYTOX Green nucleic acid stain, Thiazole Orange, TOTO 1, YO, PRO 1, and YOYO 1.

U-FYW: Specifically designed for yellow excitations with an excitation filter range of 540-585 nm and an emission filter at 600 nm. It can be used with the following fluorophores: HcRed, mCherry, mRFP, mStrawberry, Alexa Fluor 568 & 594, APC, Texas Red, Cy3.5